Organic CMOS circuits generally comprise an N-type organic MOS transistor and a P-type organic MOS transistor, sharing a common gate as well as a drain and a common source. Although organic technology provides a number of advantages, for example, in terms of manufacturing cost, the semiconductor materials forming the transistors however degrade under the effect of ultraviolet rays which break their organic chains, and accordingly the electron bonds inducing the semiconductor effect. For example, an exposure to strong ultraviolet radiation largely destroys the semiconductor effect of an N-type organic semiconductor material, with ratio Ion/Ioff of the on-state current Ion to the off-state current Ioff of an N-type organic transistor falling from −6 decades to −1 decade, thereby making the transistor non-functional.
A CMOS circuit may be submitted to a first ultraviolet radiation (UV) on manufacturing thereof due to the manufacturing techniques used, and to a second type of ultraviolet radiation when it is being used, for example, solar ultraviolet rays.
Generally, to manufacture a semiconductor element on a surface of a support, a layer of semiconductor material is first deposited all over said surface, after which an etching is performed to remove the excess semiconductor material to only leave the desired semiconductor element. Now, certain etchings, particularly plasma etchings comprising bombarding the material to be removed by means of an ionized gas, generate a high quantity of ultraviolet rays and are thus not appropriate to define an organic semiconductor element.
Further, during its lifetime, a CMOS circuit is submitted to ultraviolet rays, particularly of solar origin, and with no specific measure, a degradation of the semiconductor materials forming the CMOS circuit can be observed.